Field of the Invention
The present invention relates to a processing apparatus such as a cutting apparatus for cutting a workpiece such as a semiconductor wafer and a laser processing apparatus for performing laser processing to such a workpiece.
Description of the Related Art
In a semiconductor device fabrication process, a plurality of crossing division lines are formed on the front side of a substantially disk-shaped semiconductor wafer to thereby define a plurality of separate regions where a plurality of semiconductor devices such as ICs and LSIs are respectively formed. The semiconductor wafer thus having the plural semiconductor devices is cut along the division lines to thereby divide the regions where the semiconductor devices are formed from each other, thus manufacturing the individual semiconductor devices as chips. Further, a gallium nitride compound semiconductor or the like is formed on the front side of a sapphire substrate to obtain an optical device wafer. The optical device wafer is also cut along the division lines to thereby divide the regions where a plurality of optical devices such as light emitting diodes and laser diodes are formed from each other, thus manufacturing the individual optical devices as chips.
Cutting of such a wafer along the division lines is usually performed by using a cutting apparatus or a laser processing apparatus. The cutting apparatus includes workpiece holding means for holding a workpiece, cutting means for cutting the workpiece held by the workpiece holding means as supplying a processing water to the workpiece, feeding means for moving the workpiece holding means in a feeding direction, bellows means provided on the opposite sides of the workpiece holding means in the feeding direction so as to cover the feeding means and adapted to be moved together with the workpiece holding means in the feeding direction, the bellows means being expansible and contractable in the feeding direction, and guide means for guiding the movement of the bellows means in the feeding direction (see Japanese Patent Laid-open No. 2002-66866, for example).
Further, the laser processing apparatus includes workpiece holding means for holding a workpiece, laser beam applying means for applying a laser beam to the workpiece held by the workpiece holding means, feeding means for moving the workpiece holding means in a feeding direction, bellows means provided on the opposite sides of the workpiece holding means in the feeding direction so as to cover the feeding means and adapted to be moved together with the workpiece holding means in the feeding direction, the bellows means being expansible and contractable in the feeding direction, and guide means for guiding the movement of the bellows means in the feeding direction (see Japanese Patent Laid-open No. 2007-201178, for example).
In each case, the bellows means is provided with a plurality of support members arranged at several positions in the feeding direction for preventing the slack of the bellows means in such a manner as to slide in contact with the guide means. Each support member is formed of a low-friction resin such as Teflon (registered trademark) and nylon or provided by a bearing or the like, so as to reduce the friction between each support member and the guide means.